Analyst argues that Windows RT is all Microsoft could create before it fell further behind in tablet race

Microsoft may have simply run out of time with Windows RT, an analyst said today.

Windows RT, the name Microsoft slapped on the OS earlier this week after calling it "Windows on ARM," or WOA, for months, is the forked version of Windows 8 designed to run on devices powered by ARM SoCs, or system-on-a-chip.

ARM SoCs are the de facto powerhouses that run most smartphones and tablets, including Apple's iPad.

"This is pure speculation on my part, but it seems like they had to make a trade-off with Windows RT," said Michael Cherry, an analyst with Directions on Microsoft, a Kirkland, Wash.-based research firm that specializes in tracking Microsoft's moves. "What we're hearing now about Windows RT is a function of time and how they wanted the thing to behave. It seems to me that the a key goal was to get battery life decent and keep the weight [of devices] down."

Microsoft may have succeeded there by simply getting a version of Windows to run on the power-sipping ARM architecture. But other features or components, Cherry believes, fell by the wayside to meet that primary goal.

"They didn't have to time to get everything in there," Cherry said.

Cherry was referring to gaps in Windows RT's feature set, particularly the lack of "domain joining," the ability to connect to a corporate Windows network and the lack of support for Group Policies, one of the ways IT administrators use to manage Windows devices.

Windows RT differs in even bigger ways from Windows 8, which runs on x86/64 hardware powered by Intel and AMD processors: The OS cannot run existing Windows applications, and with the exception of some Microsoft-made components, lacks a "desktop" mode.

"Application compatibility is going to be an important consideration for enterprises considering [tablets] running Windows 8 and Windows RT," said Al Gillen of IDC in an interview earlier this week.

Gillen saw Windows RT as unlikely to win approval by enterprises because of its inability to run traditional Windows software. Instead, companies that want to equip their workforces with Windows tablets will probably look hardest at those powered by Windows 8, which does run existing applications -- even if they consume more power, and as a result, are heavier and larger because they must house a bigger battery.

"I think you can take Windows RT off the table for enterprises," he said.

"When we first heard of WOA, we all assumed Microsoft would make Windows [software] run on it," said Cherry. "Instead, they have the amount of Windows on it that they could get to run on it. Given more time, they could have done more."

Time was a factor because Microsoft has fallen seriously behind rivals Apple and Google, said Cherry, who noted that Apple's iPad is already in its third-generation.

Cherry expects Microsoft to fill in some of the blanks in Windows RT down the road, perhaps by adding the ability of those devices to support domain joining or support Group Policies.

Omissions from the feature set of Windows RT are leaving analysts increasingly skeptical that enterprises will gravitate toward tablets running the new forked version of Windows. Is Windows RT on tablets DOA because it lacks needed enterprise features?

Another option for Microsoft would be to simply wait for the appearance of lower-powered Intel processors that can compete on battery longevity with ARM, then push Windows 8, not Windows RT, for tablets.

But that carries some risk, and not only in the delays that make Microsoft fall even further behind Apple's iOS and Google's Android.

"They could end up outrunning the hardware that it's meant to run on," said Cherry, if Intel isn't able to produce chips competitive on battery life with ARM. Cherry cited Windows Vista -- Microsoft's 2007 operating system failure -- as an example of the same phenomenon, when the OS required more than the then-current hardware was able to provide.

"It's going to be some time before Intel's SoC [system-on-a-chip] is up to the same battery life as ARM," Cherry said.

Microsoft has not yet disclosed a release date for either Windows RT or Windows 8, or said when devices running the former will go on sale. Yesterday, a Microsoft executive said only that development of both operating systems was "on our schedule," but did not say what that schedule was.

Most analysts expect Windows 8 to launch in the fourth quarter, perhaps in October, which would give computer makers the chance to sell new PCs and devices during the holidays.